RELATED APPLICATIONS
This application is related to the following co-pending applications, all assigned to EATON CORPORATION, the assignee of this application:
Ser. No. 09/053,089 96-TRN-263! mailed Apr. 1, 1998 and titled RANGE SHIFT CONTROL PA1 Ser. No. 09/053,093 97-TRN-561! mailed Apr. 1, 1998 and titled ADAPTIVE UPSHIFT JAW CLUTCH ENGAGEMENT CONTROL PA1 Ser. No. 09/053,092 97-TRN-566! mailed Apr. 1, 1998 and titled ENGINE FUEL CONTROL FOR COMPLETING SHIFTS IN CONTROLLER-ASSISTED, MANUALLY SHIFTED TRANSMISSIONS PA1 Ser. No. 09/053,095 97-TRN-567! mailed Apr. 1, 1998 and titled DYNAMIC RANGE SHIFT ACTUATION PA1 Ser. No. 09/053,091 98-TRN-067! mailed Apr. 1, 1998 and titled JAW CLUTCH ENGAGEMENT CONTROL FOR ASSISTED, MANUALLY SHIFTED, SPLITTER-TYPE TRANSMISSION SYSTEM PA1 Ser. No. 09/053,181 98-TRN-101! mailed Apr. 1, 1998 and titled ADAPTIVE SPLITTER ACTUATOR ENGAGEMENT FORCE CONTROL PA1 Ser. No. 08/902,603 filed Aug. 7, 1997 and titled PARIALLY AUTOMATED, LEVER-SHIFTED MECHANICAL TRANSMISSION SYSTEM PA1 Ser. No. 08/990678 97-rTRN-495! mailed Dec. 11, 1997 and titled ASSISTED LEVER-SHIFTED TRANSMISSION.
1. Field of the Invention
The present invention relates to a control system/method for controlling automatically implemented and/or assisted shifting. In particular, the present invention relates to automatically implemented and/or assisted shifting in a transmission (such as a compound transmission having a main section shifted by a manually operated shift lever or shift selector) as a function of the sensed presence or absence of a main section neutral condition. More particularly, the present invention relates to controls for such shifting which determine if the main transmission section is in neutral or is engaged in response to sensed shift lever position and which will vary the shift lever positions at which a main section neutral condition is declared in response to sensed vehicle operating conditions.
2. Description of the Prior Art
Compound manually shifted mechanical transmissions of the range, splitter and/or combined range/splitter type are in wide use in heavy-duty vehicles and are well known in the prior art, as may be seen by reference to U.S. Pat. Nos. 4,754,665; 5,272,929; 5,370,013 and 5,390,561, 5,546,823; 5,609,062 and 5,642,643, the disclosures of which are incorporated herein by reference. Typically, such transmissions include a main section shifted directly or remotely by a manual shift lever and one or more auxiliary sections connected in series therewith. The auxiliary sections most often were shifted by a slave actuator, usually pneumatically, hydraulically, mechanically and/or electrically operated, in response to manual operation of one or more master switches. Shift controls for such systems by be seen by reference to U.S. Pat. Nos. 4,455,883; 4,550,627; 4,899,607; 4,920,815; 4,974,468; 5,000,060; 5,272,931; 5,281,902; 5,222,404 and 5,350,561, the disclosures of which are incorporated herein by reference.
Fully or partially automated transmission systems wherein a microprocessor-based electronic control unit (ECU) receives input signals indicative of various system operating conditions and processes same according to logic rules to issue command output signals to one or more system actuators are known in the prior art, as may be seen by reference to U.S. Pat. Nos. 4,361,060; 4,593,580; 4,595,986; 4,850,236; 5,435,212; 5,582,069; 5,582,558; 5,620,392; 5,651,292 and 5,679,096; 5,682,790; the disclosures of which are incorporated herein by reference.
These systems often used the sensed engaged or neutral condition of the transmission and/or transmission main section as an important control parameter.